HRR Colour Vision Test - Colour Vision Test - Kay Pictures
HRR Digital Diagnostic Color Testing | Chart2020
Pseudo-Isochromatic Plates for Color Perception, American Opical Company, 1st Ed. [1940]. *Note: The aging of this book & potential ink/page discolouration is not suitable for current testing standards. Posted as a historical
HRR Color Test
School Health HRR Pseudoisochromatic Plates 4th Ed.
HRR Standard Pseudoisochromatic Test, 4th Edition – Good-Lite
The Evolution of Color Vision Testing (Ishihara, HRR, Dvorine, and mor – Waggoner Diagnostics